SpringのschemaResolaver

26166 ワード
XML
Spring解析xmlは以上を参考にして、カスタムschemaを指定して、Jdkで提供されるxml API解析xmlを使用します.
次にSpringは自分のschemaに対して、自分で定義したxml元素を解析してSpringのBeanに注入します.
Springの高拡張性を維持するために、ユーザーはSpringに基づいて最大限に開放することができます.ここではSchema Resolaverを採用しています.解析器は最も基本的なDockment Elementを採用しています.
ここでは基本的なSpringのプラグインシステムではないが、理由は同じです.

package org.frame.base.xml.jdk.bk;

import java.io.IOException;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.frame.base.xml.jdk.Contact;
import org.frame.base.xml.jdk.ContactName;
import org.frame.base.xml.jdk.MaySimpleSaxErrorHandler;
import org.frame.base.xml.jdk.MyPluggableSchemaResolver;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

/**
 * Spring     schema,      schema   ，     Spring   
 * 
 * @author ycl
 * @version 1.0 2012-12-17   4:59:08
 * @since 1.0
 * 
 */
public class TestSpringNamespaceHandler {
	protected final static Log logger = LogFactory.getLog(TestSpringNamespaceHandler.class);

	public static MyNamespaceHandlerResolver namespaceHandlerResolver = new DefaultMyNamespaceHandlerResolver();

	public static void main(String[] args) {
		// set jaxp debug
		System.setProperty("jaxp.debug", "1");
		DocumentBuilderFactory builderFactory = DocumentBuilderFactory
				.newInstance();

		//         
		builderFactory.setNamespaceAware(true);
		builderFactory.setValidating(true);
		builderFactory.setIgnoringComments(true);
		builderFactory.setAttribute(
				"http://java.sun.com/xml/jaxp/properties/schemaLanguage",
				"http://www.w3.org/2001/XMLSchema");
		//     xsd，      schemaLanguage schema  .

		ErrorHandler errorHandler = new MaySimpleSaxErrorHandler(logger);
		//      
		EntityResolver entityResolver = new MyPluggableSchemaResolver(
				TestDocumentBuilderFactory.class.getClassLoader());
		//      

		Document document = parse(builderFactory, getInputSource(),
				entityResolver, errorHandler);

		print(document);
		printByHander(document);
	}

	private static void printByHander(Document document){
		Map context = new HashMap();
		Element root = document.getDocumentElement();

		String namespaceUri = getNamespaceURI(root);
		MyNamespaceHandler handler = namespaceHandlerResolver.resolve(namespaceUri); 
		handler.parse((Element) root,context); 
		//     
		parserElement(root,context); 
		Contact contact = (Contact)context.get("contact");
		System.out.println(contact);
	}

	private static void parserElement(Element root,Map context) { 
		NodeList nodes = root.getChildNodes();
		if(nodes!=null&&nodes.getLength()>0){
			for (int i = 0; i < nodes.getLength(); i++) {
				Node node = nodes.item(i);  
				String namespaceUri = getNamespaceURI(node);
				if(namespaceUri!=null){
					MyNamespaceHandler handler = namespaceHandlerResolver.resolve(namespaceUri); 
					handler.parse((Element) node,context);
					parserElement((Element)node,context);
				}
			}
		}
	}

	private static void print(Document document) {
		Element root = document.getDocumentElement();

		List contactNameList = new ArrayList();

		ContactName contactItem;

		//      
		NodeList nodes = root.getChildNodes();

		/**
		 * code this is so tied.
		 */
		for (int i = 0; i < nodes.getLength(); i++) {
			Node node = nodes.item(i); 
			if (node instanceof Element) {
				// a child element to process
				Element child = (Element) node;
				String width = child.getAttribute("width");
				contactItem = new ContactName();
				contactItem.setWidth(width);
				NodeList itemSub = node.getChildNodes();
				for (int j = 0; j < itemSub.getLength(); j++) {
					Node itemSubNode = itemSub.item(j);
					if (itemSubNode instanceof Element) {
						if (((Element) itemSubNode).getTagName().equals("uic")) {
							contactItem.setUid(itemSubNode.getTextContent());
						} else if (((Element) itemSubNode).getTagName().equals(
								"fullName")) {
							contactItem.setFullName(itemSubNode
									.getTextContent());
						}
					}
				}
				contactNameList.add(contactItem);
			}
		}
		System.out.println(contactNameList);
	}

	/**
	 *      namespace
	 * @param node
	 * @return
	 */
	public static String getNamespaceURI(Node node) {
		return node.getNamespaceURI();
	}


	private static InputSource getInputSource() {
		StringBuffer xml = new StringBuffer(
				"");
		xml.append("");
		xml.append("");
		xml.append("");
		xml.append("1");
		xml.append("ycl1");
		xml.append("");

		xml.append("");
		xml.append("1 06:05 Jutarnji]]> 2");
		xml.append("ycl2");
		xml.append("");

		xml.append("");

		InputSource is = new InputSource(new StringReader(xml.toString()));
		return is;
	}

	private static Document parse(DocumentBuilderFactory builderFactory,
			InputSource is, EntityResolver entityResolver,
			ErrorHandler errorHandler) {
		DocumentBuilder builder = null;

		Document document = null;
		try {
			builder = builderFactory.newDocumentBuilder();
			if (entityResolver != null) {
				builder.setEntityResolver(entityResolver);
			}
			if (errorHandler != null) {
				builder.setErrorHandler(errorHandler);
			}
			document = builder.parse(is);
		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		} catch (SAXException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return document;
	}
}

テストクラスは主にschemaを使って、schema Resolaverを定義します.

package org.frame.base.xml.jdk.bk;


public interface MyNamespaceHandlerResolver {

	/**
	 *   schema     name handler
	 * @param namespaceUri
	 * @return
	 */
	MyNamespaceHandler resolve(String namespaceUri);
}


/*
 * Copyright 2002-2009 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.frame.base.xml.jdk.bk;

import java.io.IOException;
import java.util.Map;
import java.util.Properties;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.FatalBeanException;
import org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader;
import org.springframework.beans.factory.xml.NamespaceHandler;
import org.springframework.beans.factory.xml.NamespaceHandlerResolver;
import org.springframework.core.io.support.PropertiesLoaderUtils;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.CollectionUtils;

/**
 * Default implementation of the {@link NamespaceHandlerResolver} interface.
 * Resolves namespace URIs to implementation classes based on the mappings
 * contained in mapping file.
 *
 * 
By default, this implementation looks for the mapping file at
 * META-INF/spring.handlers, but this can be changed using the
 * {@link #DefaultNamespaceHandlerResolver(ClassLoader, String)} constructor.
 *
 * @author Rob Harrop
 * @author Juergen Hoeller
 * @since 2.0
 * @see NamespaceHandler
 * @see DefaultBeanDefinitionDocumentReader
 */
public class DefaultMyNamespaceHandlerResolver implements MyNamespaceHandlerResolver {

	/**
	 * The location to look for the mapping files. Can be present in multiple JAR files.
	 */
	public static final String DEFAULT_HANDLER_MAPPINGS_LOCATION = "META-INF/myschema.handlers";


	/** Logger available to subclasses */
	protected final Log logger = LogFactory.getLog(getClass());

	/** ClassLoader to use for NamespaceHandler classes */
	private final ClassLoader classLoader;

	/** Resource location to search for */
	private final String handlerMappingsLocation;

	/** Stores the mappings from namespace URI to NamespaceHandler class name / instance */
	private volatile Map handlerMappings;


	/**
	 * Create a new DefaultNamespaceHandlerResolver using the
	 * default mapping file location.
	 * 
This constructor will result in the thread context ClassLoader being used
	 * to load resources.
	 * @see #DEFAULT_HANDLER_MAPPINGS_LOCATION
	 */
	public DefaultMyNamespaceHandlerResolver() {
		this(null, DEFAULT_HANDLER_MAPPINGS_LOCATION);
	}

	/**
	 * Create a new DefaultNamespaceHandlerResolver using the
	 * default mapping file location.
	 * @param classLoader the {@link ClassLoader} instance used to load mapping resources
	 * (may be null, in which case the thread context ClassLoader will be used)
	 * @see #DEFAULT_HANDLER_MAPPINGS_LOCATION
	 */
	public DefaultMyNamespaceHandlerResolver(ClassLoader classLoader) {
		this(classLoader, DEFAULT_HANDLER_MAPPINGS_LOCATION);
	}

	/**
	 * Create a new DefaultNamespaceHandlerResolver using the
	 * supplied mapping file location.
	 * @param classLoader the {@link ClassLoader} instance used to load mapping resources
	 * may be null, in which case the thread context ClassLoader will be used)
	 * @param handlerMappingsLocation the mapping file location
	 */
	public DefaultMyNamespaceHandlerResolver(ClassLoader classLoader, String handlerMappingsLocation) {
		Assert.notNull(handlerMappingsLocation, "Handler mappings location must not be null");
		this.classLoader = (classLoader != null ? classLoader : ClassUtils.getDefaultClassLoader());
		this.handlerMappingsLocation = handlerMappingsLocation;
	}


	/**
	 * Locate the {@link NamespaceHandler} for the supplied namespace URI
	 * from the configured mappings.
	 * @param namespaceUri the relevant namespace URI
	 * @return the located {@link NamespaceHandler}, or null if none found
	 */
	public MyNamespaceHandler resolve(String namespaceUri) {
		Map handlerMappings = getHandlerMappings();
		Object handlerOrClassName = handlerMappings.get(namespaceUri);
		if (handlerOrClassName == null) {
			return null;
		}
		else if (handlerOrClassName instanceof MyNamespaceHandler) {
			return (MyNamespaceHandler) handlerOrClassName;
		}
		else {
			String className = (String) handlerOrClassName;
			try {
				Class> handlerClass = ClassUtils.forName(className, this.classLoader);
				if (!MyNamespaceHandler.class.isAssignableFrom(handlerClass)) {
					throw new FatalBeanException("Class [" + className + "] for namespace [" + namespaceUri +
							"] does not implement the [" + MyNamespaceHandler.class.getName() + "] interface");
				}
				MyNamespaceHandler namespaceHandler = (MyNamespaceHandler) BeanUtils.instantiateClass(handlerClass);
				namespaceHandler.init();
				handlerMappings.put(namespaceUri, namespaceHandler);
				return namespaceHandler;
			}
			catch (ClassNotFoundException ex) {
				throw new FatalBeanException("NamespaceHandler class [" + className + "] for namespace [" +
						namespaceUri + "] not found", ex);
			}
			catch (LinkageError err) {
				throw new FatalBeanException("Invalid NamespaceHandler class [" + className + "] for namespace [" +
						namespaceUri + "]: problem with handler class file or dependent class", err);
			}
		}
	}

	/**
	 * Load the specified NamespaceHandler mappings lazily.
	 */
	private Map getHandlerMappings() {
		if (this.handlerMappings == null) {
			synchronized (this) {
				if (this.handlerMappings == null) {
					try {
						Properties mappings =
								PropertiesLoaderUtils.loadAllProperties(this.handlerMappingsLocation, this.classLoader);
						if (logger.isDebugEnabled()) {
							logger.debug("Loaded NamespaceHandler mappings: " + mappings);
						}
						Map handlerMappings = new ConcurrentHashMap();
						CollectionUtils.mergePropertiesIntoMap(mappings, handlerMappings);
						this.handlerMappings = handlerMappings;
					}
					catch (IOException ex) {
						throw new IllegalStateException(
								"Unable to load NamespaceHandler mappings from location [" + this.handlerMappingsLocation + "]", ex);
					}
				}
			}
		}
		return this.handlerMappings;
	}


	@Override
	public String toString() {
		return "NamespaceHandlerResolver using mappings " + getHandlerMappings();
	}

}

私の怠けを許してください.裸のcopy Springソースです.

public interface MyNamespaceHandler {

	public void init();
	public ContactName parse(Element element,Map context);
}

package org.frame.base.xml.jdk.bk;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.frame.base.xml.jdk.ContactName;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.FatalBeanException;
import org.springframework.core.io.support.PropertiesLoaderUtils;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.CollectionUtils;
import org.w3c.dom.Element;

public class SchemaNamespaceHandler implements MyNamespaceHandler {

	/**
	 * The location to look for the mapping files. Can be present in multiple JAR files.
	 */
	public static final String DEFAULT_HANDLER_MAPPINGS_LOCATION = "META-INF/schema/contact.handler";

	/** Logger available to subclasses */
	protected final Log logger = LogFactory.getLog(getClass());

	/** ClassLoader to use for NamespaceHandler classes */
	private final ClassLoader classLoader;

	/** Resource location to search for */
	private final String handlerMappingsLocation;

	/** Stores the mappings from namespace URI to NamespaceHandler class name / instance */
	private volatile Map handlerMappings; 

	public SchemaNamespaceHandler(){
		this(null, DEFAULT_HANDLER_MAPPINGS_LOCATION);
	}

	public SchemaNamespaceHandler(ClassLoader classLoader) {
		this(classLoader, DEFAULT_HANDLER_MAPPINGS_LOCATION);
	}

	public SchemaNamespaceHandler(ClassLoader classLoader, String handlerMappingsLocation) {
		Assert.notNull(handlerMappingsLocation, "Handler mappings location must not be null");
		this.classLoader = (classLoader != null ? classLoader : ClassUtils.getDefaultClassLoader());
		this.handlerMappingsLocation = handlerMappingsLocation;
	}


	@Override
	public void init() {
		// TODO Auto-generated method stub 
	}

	@Override
	public ContactName parse(Element element,Map context) { 
		return resolve(element.getLocalName()).parse(element,context);
	}

	public MyNamespaceHandler resolve(String namespaceUri) {
		Map handlerMappings = getHandlerMappings();
		Object handlerOrClassName = handlerMappings.get(namespaceUri);
		if (handlerOrClassName == null) {
			return null;
		}
		else if (handlerOrClassName instanceof MyNamespaceHandler) {
			return (MyNamespaceHandler) handlerOrClassName;
		}
		else {
			String className = (String) handlerOrClassName;
			try {
				Class> handlerClass = ClassUtils.forName(className, this.classLoader);
				if (!MyNamespaceHandler.class.isAssignableFrom(handlerClass)) {
					throw new FatalBeanException("Class [" + className + "] for namespace [" + namespaceUri +
							"] does not implement the [" + MyNamespaceHandler.class.getName() + "] interface");
				}
				MyNamespaceHandler namespaceHandler = (MyNamespaceHandler) BeanUtils.instantiateClass(handlerClass);
				namespaceHandler.init();
				handlerMappings.put(namespaceUri, namespaceHandler);
				return namespaceHandler;
			}
			catch (ClassNotFoundException ex) {
				throw new FatalBeanException("NamespaceHandler class [" + className + "] for namespace [" +
						namespaceUri + "] not found", ex);
			}
			catch (LinkageError err) {
				throw new FatalBeanException("Invalid NamespaceHandler class [" + className + "] for namespace [" +
						namespaceUri + "]: problem with handler class file or dependent class", err);
			}
		}
	}

	/**
	 * Load the specified NamespaceHandler mappings lazily.
	 */
	private Map getHandlerMappings() {
		if (this.handlerMappings == null) {
			synchronized (this) {
				if (this.handlerMappings == null) {
					try {
						Properties mappings =
								PropertiesLoaderUtils.loadAllProperties(this.handlerMappingsLocation, this.classLoader);
						if (logger.isDebugEnabled()) {
							logger.debug("Loaded NamespaceHandler mappings: " + mappings);
						}
						Map handlerMappings = new ConcurrentHashMap();
						CollectionUtils.mergePropertiesIntoMap(mappings, handlerMappings);
						this.handlerMappings = handlerMappings;
					}
					catch (IOException ex) {
						throw new IllegalStateException(
								"Unable to load NamespaceHandler mappings from location [" + this.handlerMappingsLocation + "]", ex);
					}
				}
			}
		}
		return this.handlerMappings;
	}


	@Override
	public String toString() {
		return "NamespaceHandlerResolver using mappings " + getHandlerMappings();
	}


}

次に私達の配置ファイルを見ます.
myschema.handers

http\://www.ycl.com/schema/schema=org.frame.base.xml.jdk.bk.SchemaNamespaceHandler
contact.handler

contact=org.frame.base.xml.jdk.bk.ContactHandler
item=org.frame.base.xml.jdk.bk.ItemHandler
uic=org.frame.base.xml.jdk.bk.UicHandler
fullName=org.frame.base.xml.jdk.bk.FullNameHandler
ここではxmlの元素ごとにハードラーを定義しています.

package org.frame.base.xml.jdk.bk;

import java.util.Map;

import org.frame.base.xml.jdk.Contact;
import org.frame.base.xml.jdk.ContactName;
import org.w3c.dom.Element;

/**
 *               
 *
 * @author ycl
 * @version 1.0 2012-12-18   9:32:12
 * @since 1.0
 *
 */
public class ContactHandler implements MyNamespaceHandler {

	@Override
	public void init() {
		// TODO Auto-generated method stub

	}

	@Override
	public ContactName parse(Element element,Map context) {
		Contact contactName = new Contact(); 
		context.put("contact", contactName);
		return null;
	}

}


package org.frame.base.xml.jdk.bk;

import java.util.Map;

import org.frame.base.xml.jdk.Contact;
import org.frame.base.xml.jdk.ContactName;
import org.frame.base.xml.jdk.Item;
import org.w3c.dom.Element;

public class ItemHandler implements MyNamespaceHandler {

	@Override
	public void init() {
		// TODO Auto-generated method stub

	}

	@Override
	public ContactName parse(Element element, Map context) {
		Contact contactName = (Contact) context.get("contact");
		String width = element.getAttribute("width");
		Item item = new Item();
		item.setWidth(width);
		contactName.addItem(item);
		context.put("curentItem", item);
		return null;
	}

}


package org.frame.base.xml.jdk.bk;

import java.util.Map;

import org.frame.base.xml.jdk.Contact;
import org.frame.base.xml.jdk.ContactName;
import org.frame.base.xml.jdk.Item;
import org.w3c.dom.Element;

public class UicHandler implements MyNamespaceHandler {

	@Override
	public void init() {
		// TODO Auto-generated method stub

	}

	@Override
	public ContactName parse(Element element, Map context) {
		Item item = (Item)context.get("curentItem");
		String uic = element.getTextContent();
		item.setUic(uic);
		return null;
	}

}


package org.frame.base.xml.jdk.bk;

import java.util.Map;

import org.frame.base.xml.jdk.ContactName;
import org.frame.base.xml.jdk.Item;
import org.w3c.dom.Element;

public class FullNameHandler implements MyNamespaceHandler {

	@Override
	public void init() {
		// TODO Auto-generated method stub

	}

	@Override
	public ContactName parse(Element element, Map context) {
		Item item = (Item)context.get("curentItem");
		String fullName = element.getTextContent();
		item.setFullName(fullName);
		return null;
	}

}

もちろん、ここの図は簡単で、全体のxmlを解析しますが、reolverでは自分の必要なxml元素を自分のConteextの中に解析できます.contextは任意の中のものを置くことができます.これは文脈です.
出力データは以下の通りです

20121218-10:56:08 main org.springframework.beans.factory.xml.PluggableSchemaResolver Loading schema mappings from [META-INF/myschema.schemas]
20121218-10:56:08 main org.springframework.beans.factory.xml.PluggableSchemaResolver Loaded schema mappings: {http://www.ycl.com/schema/schema.xsd=org/frame/base/xml/jdk/schema.xsd}
20121218-10:56:08 main org.springframework.beans.factory.xml.PluggableSchemaResolver Found XML schema [http://www.ycl.com/schema/schema.xsd] in classpath: org/frame/base/xml/jdk/schema.xsd
[uid:1,fullName:ycl1,width:10, uid:1 06:00 Vesti
06:05 Jutarnji 2,fullName:ycl2,width:11]
20121218-10:56:08 main org.frame.base.xml.jdk.bk.DefaultMyNamespaceHandlerResolver Loaded NamespaceHandler mappings: {http://www.ycl.com/schema/schema=org.frame.base.xml.jdk.bk.SchemaNamespaceHandler}
20121218-10:56:08 main org.frame.base.xml.jdk.bk.SchemaNamespaceHandler Loaded NamespaceHandler mappings: {contact=org.frame.base.xml.jdk.bk.ContactHandler, uic=org.frame.base.xml.jdk.bk.UicHandler, item=org.frame.base.xml.jdk.bk.ItemHandler, fullName=org.frame.base.xml.jdk.bk.FullNameHandler}
[width:10,uic:1,fullName:ycl1,sex:null, width:11,uic:1 06:00 Vesti
06:05 Jutarnji 2,fullName:ycl2,sex:null]

ここではカスタムのhandlerと自分が望む結果を出力できます.
このような解析モードを使うと、xml構造に関係する必要はなく、Javaオブジェクトとの関係は不要です.
あなたが関心を持っているのはxmlだけです.私はxmlの中の元素を解析したいです.xml元素とJavaオブジェクトには必然的な関係がありません.これも伝説の中の「結合」ですか?
私はただ各要素をHandlerに設計しただけです.この解析モードを使えば、属性を使うとコードが短縮され、分かりやすくなります.
SpringはBeanの設計に対してもサブ要素が許されています.それはProptiesです.実は属性であり、サブ要素に置くだけでもより美しく見えます.論理がもっとはっきりしていて、Ben注入の強い優位性がもっと際立っています.
Spring.NET学習ノート(1)-基本依存注入
tenssor flowは二つのtensorが完全に同じかどうかを判断します.